1. Field of the Invention
The present invention relates to a wiper apparatus which is installed on a vehicle or the like, and particularly to a wiper apparatus in which a holding member for holding a wiper motor and an elongated supporting pipe fixed to a vehicle body and supporting a wiper linkage, are welded together.
2. Description of the Related Art
Conventionally, in a wiper apparatus installed on a vehicle or the like, a wiper motor is fixed with mounting members, such as bolts and nuts, to a mounting portion of a holding member which comprises the mounting portion and a grip portion. On the inner periphery of the grip portion, a plurality of protruding portions is provided, each with a substantially spherical shape formed by embossing. A weld portion is respectively formed between each of the plurality of protruding portions and an elongated supporting pipe for supporting a wiper linkage fixed to a vehicle body, thereby causing the wiper motor to be held by the holding member and the supporting pipe to the wiper linkage.
However, with the aforementioned arrangement, when a load is imparted to the wiper linkage, e.g., due to the locking of the wiper arm, and vibration of the vehicle body during running of the vehicle, moment in a circumferential direction of the supporting pipe may be generated in the mounting portion of the holding member which holds the wiper motor. As a result, the bending moment which is accompanied with the aforementioned moment is generated in the weld portions between the grip portion and the supporting pipe. Since the aforementioned weld portion comprises a plurality of substantially spherical protruding portions, i.e., it is formed by spot welding, sufficient welding strength against the bending moment cannot be obtained on the weld portion between the holding member and the supporting pipe. As a result, it was not reliability sufficient for holding the wiper motor to the wiper linkage.